Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!EE.ECN.PURDUE.EDU!steele
From: steele@EE.ECN.PURDUE.EDU (Richard Steele)
Newsgroups: sci.electronics
Subject: Data Over Voice
Keywords: DOV, Data Over Voice
Message-ID: <8912061817.AA28752@en.ecn.purdue.edu>
Date: 6 Dec 89 18:17:01 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: steele@en.ecn.purdue.edu (Richard Steele)
Distribution: usa
Organization: Purdue University Engineering Computer Network
Lines: 21

Thanks to everyone who responded to my question about crest factors; the
subject, though now I see a rather simple one in concept, has been bothering
me for a while.  Now, for another one:

Here at Pudue U., we now have access to something called data over voice
(DOV) units.  These are small boxes, about the size of a regular modem,
that gives the user a 9600 bps asynchronous data line to the University
computer.  Not only is the bugger faster than a modem, _but it leaves
the phone free for regular use_.  We can still receive and make calls
with the DOV working with no obvious distortion on the line.  Thus, in
addition to having a reasonably fast connection (and I used to think a
2400 baud modem was speedy!), I don't have to take the wrath of my
roomates for hogging the phone line all night long.

Question:  How would something like this work?  The phone company _does_
need to make some changes to their central switch (or something like
that -- although I'm a EE, telephony is definately _not_ my specialty. :-) )

So, what magic is involved here?  Thanks again to all who respond...

Richard A. Steele                                            Purdue University